Additive manufacturing encompasses a class of fabrication techniques in which structures are built in a “bottom up” mode. This paradigm is gaining acceptance as a low-cost production method for custom-designed components. However, additive fabrication remains a relatively slow process that is often materials-limited.
To enable high throughput patterning, several techniques have been recently modified to incorporate parallelization schemes. For example, inkjet printing utilizes silicon-based microfluidic printheads to eject microscale droplets via resistance heating or piezoelectric transducers. Massively parallel variants of dip pen nanolithography, such as polymer pen lithography and hard-tip, soft-spring lithography, use multi-tip arrays composed of silicon or PDMS that deposit a low viscosity ink on a substrate to yield 2D nanoscale patterns. Parallel electrospinning simultaneously deposits nanofibers onto a substrate from independent and separate nozzles. Projection micro-stereolithography, a layer-by-layer manufacturing approach, enables fabrication via a digital micro-mirror dynamic mask, which selectively polymerizes voxels in parallel. Each of these techniques, however, requires either low viscosity inks with dilute concentrations of the desired material or a restricted set of photocurable resins.
The ability to pattern highly concentrated fluids, resins, pastes and gels in a high throughput manner would expand the palette of desirable materials and facilitate the creation of structures that exhibit minimal shrinkage and deformation. The possibility of large scale, rapid production of planar and 3D microstructured components may have broad relevance to fields such as printed electronics, solar cells, microfluidics, polishing media, novel composites, and tissue engineering.